Description: This center of mass demo will have your students scratching their heads and not believing their eyes!

Instructions: A set of 7 blocks will be provided for you to assemble in front of the class. Start with the block numbered 1 at the bottom of the pile, lined up with the edge of the table. From here, line up the markings on the blocks until the last block is in place and completely over the edge of the table.

Make sure you have the marking pointing away from you while the class is watching!

Hazards: These blocks are very heavy! Watch out for your feet, or any students under the stack.

Parts: 7 marked blocks

Purchased/Built: built

Quant. in Demo Room: 1

Demo References

Freier and Anderson

Mp-11

Stack blocks until the top block sticks out beyond any part of the bottom block.

The Physics Teacher

TPT 18(9),672

Use the center of mass of a composite object to support a block beyond the edge of the lecture bench. This article emphasizes a lab approach. Ref. AJP 23,240 (1955).

The American Journal of Physics

AJP 23(4),240

A note discussing the derivation of the harmonic series describing the leaning tower of Lire.